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United States Patent | 5,347,473 |
Hallman ,   et al. | September 13, 1994 |
An electronic calculator allows a user to quickly add up change. The user simply pushes one of the coin switches clearly marked to represent a particular coin denomination in order to add up the change. Each time a coin switch is activated, an accumulated sum is incremented by a value associated with the value of the coin denomination represented by the activated coin switch. The accumulated sum is then displayed to the user. If the user depresses the wrong coin switch, an error switch is provided which subtracts the previous entry made from the tabulated sum to arrive at the tabulated sum previous to the depression of the coin switch.
Inventors: | Hallman; Charles D. (4520 Newberry, Wayne, MI 48184); McElhone; Dennis P. (80 Groveland, Howell, MI 48843) |
Appl. No.: | 125174 |
Filed: | September 23, 1993 |
Current U.S. Class: | 708/132; 434/110 |
Intern'l Class: | G06F 003/00; G09B 019/18 |
Field of Search: | 364/709.02 434/110 273/273 |
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4752227 | Jun., 1988 | Yamin | 434/110. |
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